An example of a facet joint is found in which part of the body?

The facet joints, also known as zygapophyseal joints, are crucial components of the vertebral column found in the spine. These synovial joints are located between the articulation of the superior and inferior articular processes of adjacent vertebrae, allowing for a range of motion and stability in the spine. They play a significant role in facilitating movements such as rotation, flexion, and extension while helping to bear the loads of the upper body.

While the clavicle, rib cage, and knee are all important structures in the body, they do not contain facet joints. The clavicle connects the arm to the body and mainly involves the sternoclavicular and acromioclavicular joints. The rib cage is responsible for protecting vital organs and assisting with respiration, primarily involving costovertebral and costosternal joints, but not facet joints. The knee is a hinge joint composed of the femur, tibia, and patella, and while it has its own set of ligaments and menisci, it does not feature facet joints either.

Thus, the correct identification of the spine as containing facet joints reflects the unique structure and function of these joints within the vertebral column.